SANBORN MAPS have a rich history as research tools. Developed in the mid-19th century to assess risk for fire insurance, they have proved an invaluable tool for historical research, thanks to their meticulous detail and accuracy. The Library of Congress has digitized over 25,000 Sanborn maps in more than 3,000 US cities, all available for perusal at their website. In this case, we are using Sanborn maps to unearth different elements of the North Claiborne corridor's commercial district. In doing so, we will also identify some methodological elements – opportunities and limitations – of doing historical geographic research with Sanborn maps.
THE SANBORN COMPANY was founded in 1866 by Daniel Alfred Sanborn, as a means to provide information about building quality to fire insurance underwriters. Indeed, in the late 19th century across the US, rapid urbanization and population growth led to a growing demand for the assessment of fire risk. It wasn't long before most major cities across the country had been surveyed by Sanborn.
ALTHOUGH SANBORN discontinued fire insurance mapping midway through the 20th century, their maps remain useful geographic tools for understanding urban change across the US. Because they represented a significant amount of capital in the built envivronment, Sanborn maps followed extremely detailed standards and cartographic practices. Furthermore, they were extraordinarily detailed, providing information on building size, material, ownership, and more (all data points that an insurer would presumably want!). A critical examination of Sanborn maps helps to reveal the archival nature of cultural landscapes. Maps are power-laden objects, both telling the story of and actively producing the world they purport to represent. So, let's begin to explore the historical geographies of a street in New Orleans through Sanborn maps.